LECTURE XI 

 THE SKIN 



653. The Skin (Plate XL., 10) is a dense, porous, and very sensitive 

 structure, serving to cover and protect the body from external 

 injury. It is composed of two layers — 



1. External— the Cuticle, or Epidermis. 



2. Internal— the Dermis, True Skin, or Cutis Vera. 



The skin varies in thickness in different parts of the body. It is 

 fine and soft where much motion is required, and dense and thick 

 where the parts are exposed, as the back, shoulders, etc. 



654. The Cuticle, or Epidermis, is composed principally of 

 scales, which are cast off when done with, like the scales from the 

 body of a fish. It is non-sensitive. The deepest part of the 

 epidermis is known as the rete mucosum, and it is to it that the 

 skin owes its colour. 



655. The Cutis Vera (dermis, or true skin) contains the 

 sebaceous, fat, or oil glands, the sudoriparous or sweat 

 glands, the hair and hair follicles. 



656. The Sebaceous Glands {Plate XL., 10 E) secrete an oil, 

 which pours into the hair follicles for the purpose of lubricating the 

 skin and keeping it and the hair soft. 



657. Sudoriparous or Sweat Glands {Plate XL., 10 B).—lt 

 is said that there are about 2,000 pores in 1 square inch of skin for 

 the purpose of perspiration, an action which is both insensible and 

 sensible. The quantity of sweat varies very much, according to the 



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